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Our best science tells us that the universe is an ever expanding entity consisting of some 400 billion galaxies that began with a very powerful and very hot explosion from a single point precisely 13.72 billion years ago. The degree to which our best science here has advanced in the recent past is reflected by the understanding of the universe that we had just a century ago. At that time, it was thought that the universe was static and consisted of just one galaxy: our own. In the past 100 years, though, Einstein’s theory of relativity revolutionized how we understand space and time and the physical processes operating at the very largest of scales, while quantum mechanics has revolutionized how we understand these processes at the very smallest of scales. It is the development of these theories in particular that has provided us with our current understanding of the universe.
However, the picture of the universe that these theories have furnished us with still leaves us with an apparent problem: What existed before the big bang? Surely something must have existed beforehand, for if nothing existed then something (indeed everything!) came from nothing, which seems absurd. Indeed there are few things more intuitively implausible than that something can come from nothing. In the philosophical community ex nihilo, nihilo fit (from nothing, nothing comes) is appreciated to be a self evident premise, and one of only a handful of postulates that are completely indisputable.
The apparent contradiction between the universe beginning at a finite time, and the premise that something cannot come from nothing, has often been used as an argument for the existence of an uncaused cause, or creator (most often understood as God). However, in his new book ‘A Universe from Nothing: Why There is Something Rather than Nothing’ renowned physicist and cosmologist Lawrence Krauss argues that a full understanding of the science that has yielded our current picture of the universe also allows us to see that something can indeed come from nothing. Thus, for Krauss, science can in fact do the work that it is often thought only God could manage. As Krauss puts it (borrowing a line from the physicist Steven Weinberg), science does not make it impossible to believe in God, but it does make it possible to not believe in God (p. 183). In introducing us to the science that allows for the possibility of something coming from nothing, Krauss takes us through the history and evolution of physics and cosmology over the past century, beginning with Albert Einstein’s theory of relativity in 1916. In the course of this journey we learn about what our best science says about the basic make-up of our universe (including the existence of dark matter and dark energy), as well as what our best science tells us about how the universe (likely) began and where it is (likely) heading in the future.
What follows is full executive summary of A Universe from Nothing: Why There Is Something Rather than Nothing by Lawrence Krauss.
*Before we begin, it should be mentioned that Krauss’ book is based on a public lecture that he gave in 2009 and which has since been posted on YouTube and become quite a sensation (as far as academic lectures go) with over a million hits. The reader may be interested in watching this video either before reading the present article or thereafter. Here it is:
For my money, though, the lecture given by Krauss’ colleague Michael Turner on virtually the exact same topic is even better (since it has lots of excellent visuals [which Krauss’ does not], and Turner’s sense of humour is just as entertaining as Krauss’—if not more so). The link to this lecture is here: http://www.youtube.com/watch?v=jWaOyy3WfWk&feature=related For a documentary style presentation of the story of our universe, I highly recommend this one: http://www.youtube.com/watch?v=NEZWtrvxyow&feature=related
By the time Einstein came along around the turn of the last century, Isaac Newton’s laws of physics had held sway for over two hundred years. However, there were certain observed phenomenon that did not quite square with Newton’s laws—for instance, the behaviour of electromagnetic fields. In an effort to eliminate the inconsistencies between theory and observation, Einstein introduced an alternative theory—known as the theory of relativity. While Einstein’s theory nicely resolved the inconsistencies in Newton’s laws, the implications of the theory were strange to say the least. For one, Einstein’s theory implied that space and time were not absolute, but relative, and could be bent and warped, just as things within space and time could be bent and warped. As strange as this sounds, empirical evidence was soon coming in that confirmed that the theory was in fact correct. The first bit of evidence here was how Einstein’s theory was able to account for a quirk in the orbit of Mercury, which Newton’s theory was not able to accommodate (p. 3). The real clincher came in 1919 though, when the curving of space was observed directly. As Krauss explains, “in 1919… two expeditions observed starlight curving around the sun during a solar eclipse in precisely the degree to which Einstein had predicted should happen if the presence of the sun curved the space around it” (p. 26).
Another implication of Einstein’s theory is that gravity is constantly pulling objects together, and therefore, unless there is a force acting in opposition to gravity, all objects in the universe would be on a crash course towards one another (p. 2). This was not only a rotten thing to fathom, but also contradicted the then current understanding that the universe is static (which all of the evidence [not to mention religion] supported).
In order to make his theory consistent with a static universe, Einstein postulated that a counterforce to gravity must exist, and in precisely the right amount to cancel out the force of gravity (p. 3). This force came to be called the cosmological constant (p. 57).
As the evidence regarding the true nature of the universe continued to filter in though, it turned out that the universe was not in fact static. Nor was it collapsing, though. It was actually expanding! This was first discovered in the mid 1920’s by Edwin Hubble, who used new advances in telescopic technology, in conjunction with known properties of the quality and brightness of the light from stars, to make this determination (p. 8-10). Incidentally, the very same observations that allowed Hubble to discover that the universe is expanding also allowed him to conclude that ours was not the only galaxy (p. 8). So in one fell swoop, and thanks in large part to Edwin Hubble, our picture of the universe underwent a cosmic revolution (no wonder they named a very special telescope after him :- ) Speaking of which, the pictures from this telescope are incredible. Here’s one of my favorites:
If you would like to take a look at more images from Hubble, I highly recommend you check out this link: http://hubblesite.org/gallery/album/show/
In any event, given that gravity sucks (that is, given that gravity is an attractive force), an expanding universe implies that there must be a force that opposes gravity, and that at the present time this force exceeds the force of gravity. What’s more, an expanding universe implies that the universe was once smaller, and indeed must have begun at a single point (p. 15). These findings provided part of the impetus for postulating the big bang theory of the universe: the idea that the universe began as a single hot point and exploded outward from there with enormous energy to produce what we currently have.
*For prospective buyers: To get a good indication of how this (and other) articles look before purchasing, I’ve made several of my past articles available for free. Each of my articles follows the same form and is similar in length (15-20 pages). The free articles are available here: Free Articles